Create a numeric variable for gender from character

[graceahey]

Hello-

Trying to convert a character variable for gender to a numeric.

df_enrollment_clean$sex is a string variable: "Male" or "Female." I need to convert to a 1 for males or a 2 for females. Using the below; I'm completely new to R so I appreciate the help!

Grace

sexObserved <- factor(df_enrollment_clean$sex) #This is 1 for female, 2 for male
sexObserved[df_enrollment_clean$sex=="Male"] <- "1"
sexObserved[df_enrollment_clean$sex=="Female"] <- "2"
sexObserved <- factor(sexObserved)

[joels]

recode is probably the most straightforward approach for your case, but the code below shows a few options. I've converted to numeric, rather than character/factor. Did you want the new 1 and 2 values to be coded as factor? If so, it would make more sense to keep the original coding for sex and just convert that to factor class.

library(tidyverse)

# Fake data
set.seed(2)
d = data.frame(sex = sample(c("Male","Female"), 10, replace=TRUE))
d$sex[5] = NA

d
#>       sex
#> 1    Male
#> 2    Male
#> 3  Female
#> 4  Female
#> 5    <NA>
#> 6  Female
#> 7    Male
#> 8    Male
#> 9    Male
#> 10 Female

sexObserved = recode(d$sex, "Male"=1, "Female"=2, .missing=4)

sexObserved
#>  [1] 1 1 2 2 4 2 1 1 1 2

sexObserved = ifelse(d$sex=="Male", 1, 2)

sexObserved
#>  [1]  1  1  2  2 NA  2  1  1  1  2

sexObserved = case_when(d$sex=="Male" ~ 1,
                        d$sex=="Female" ~ 2,
                        is.na(d$sex) ~ 4,
                        TRUE ~ 3)

sexObserved
#>  [1] 1 1 2 2 4 2 1 1 1 2

^{Created on 2021-02-24 by the reprex package (v1.0.0)}